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    • Welcome Squad
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    (Original post by rachelc142)
    I. am. so. fed. up. with. A. Levels.

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    3 more and then I'm done!
    And one of them's tomorrow
    We'll see how it goes
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    (Original post by 8472)
    Realised I post more in the year 10 thread than my own year group thread. :blush:

    Interested, would people say that their revision technique has gotten better each year?
    Umm, seeing as I didn't really revise for my GCSEs I guess you could say my technique has improved over the years... :lol:


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    (Original post by rachelc142)
    I. am. so. fed. up. with. A. Levels.

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    Baelieve in yourself and persevere!

    Same. I know I'm gonna fail



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    u too son, baelieve in yourself mate (Y)


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    (Original post by rachelc142)
    I. am. so. fed. up. with. A. Levels.

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    I know that feel. Every time I try to do something I just want to sleep.

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    (Original post by binarythoughts)
    Either 2340 or 2360 can't remember haha.
    I'm the eldest so I have no one to give me advice in that respect


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    (Original post by Princepieman)
    You deffo should have given it a punt. I got 2250 but decided (foolishly) not to apply.

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    So we destroyed SATS eh?
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    (Original post by _Caz_)
    I know that feel. Every time I try to do something I just want to sleep.

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    We are similar.I've got an exam in 6 days.I've been sleeping for 10 hours lol!
    • Welcome Squad
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    Welcome Squad
    Finished S2 today and it went grrrreat!
    2 more exams to go - can't wait to finish!
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    (Original post by The Clockwork Apple)
    Finished S2 today and it went grrrreat!
    2 more exams to go - can't wait to finish!
    Mine haven't even started:emo:.
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    Yo sorry for being really annoying again but you guys seem to be really good at chemistry!

    I just wanted to ask why do some carboxylic acids, e.g. lactic acid, become cyclic esters when they are heated with sulphuric acid? What's this type of reaction called? I've looked in the textbook but I can't find an answer and my teachers aren't very helpful (
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    (Original post by radhikagulati)
    Yo sorry for being really annoying again but you guys seem to be really good at chemistry!

    I just wanted to ask why do some carboxylic acids, e.g. lactic acid, become cyclic esters when they are heated with sulphuric acid? What's this type of reaction called? I've looked in the textbook but I can't find an answer and my teachers aren't very helpful (
    I think lactic acid has an -OH group as well as a -COOH, so it is an alcohol as well as an ester.

    I couldn't tell you what the reaction is called though.
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    (Original post by radhikagulati)
    Yo sorry for being really annoying again but you guys seem to be really good at chemistry!

    I just wanted to ask why do some carboxylic acids, e.g. lactic acid, become cyclic esters when they are heated with sulphuric acid? What's this type of reaction called? I've looked in the textbook but I can't find an answer and my teachers aren't very helpful (
    When you react and OH with a COOH, the bond formed is an ester bond and the process is normally called esterification.

    I'm not sure you need to know why they become cyclic because AQA don't but if I had to take a guess it'd probably be to do with stability or something.
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    (Original post by zed963)
    When you react and OH with a COOH, the bond formed is an ester bond and the process is normally called esterification.

    I'm not sure you need to know why they become cyclic because AQA don't but if I had to take a guess it'd probably be to do with stability or something.
    There was an esterification question on lactic acid and I drew a normal ester but the mark scheme came up with this weird cyclic structure so I'm vvv confused And Im doing OCR Salters not AQA unfortunately (
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    (Original post by radhikagulati)
    There was an esterification question on lactic acid and I drew a normal ester but the mark scheme came up with this weird cyclic structure so I'm vvv confused And Im doing OCR Salters not AQA unfortunately (
    Interesting,

    Do you have a pic of the structure?

    This might help http://www.chemistryrules.me.uk/cand...xylicacids.htm
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    Thanks for the link

    And it was question 2e in this paper: http://www.ocr.org.uk/Images/131296-...-by-design.pdf

    x
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    (Original post by radhikagulati)
    Thanks for the link

    And it was question 2e in this paper: http://www.ocr.org.uk/Images/131296-...-by-design.pdf

    x
    Yes it forms a cyclic structure! They each have at least one -OH and one -COOH group. It's one of the trickier questions
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    (Original post by radhikagulati)
    Yo sorry for being really annoying again but you guys seem to be really good at chemistry!

    I just wanted to ask why do some carboxylic acids, e.g. lactic acid, become cyclic esters when they are heated with sulphuric acid? What's this type of reaction called? I've looked in the textbook but I can't find an answer and my teachers aren't very helpful (
    Could this be the carboxylic acid acting as a dimer? If it is, it's because hydrogen bonds are formed between the oxygen of the carbonyl carbon and the hydrogen of the OH. Here's the link http://en.wikipedia.org/wiki/Dimer_%28chemistry%29

    No idea about the heating with H2SO4 part tho
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    (Original post by cerlohee)
    Could this be the carboxylic acid acting as a dimer? If it is, it's because hydrogen bonds are formed between the oxygen of the carbonyl carbon and the hydrogen of the OH. Here's the link http://en.wikipedia.org/wiki/Dimer_%28chemistry%29

    No idea about the heating with H2SO4 part tho
    Well I'm guessing the formed compound is a cyclic ester or SOMETHING LIKE THAT (don't judge me I don't know all these names), so H2SO4 and heat catalyses
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    How many exams has everyone got left?

    I've got 8 exams -> 4 maths, 3 physics and 1 history.
    2/10 exams finished atm.

    Crazy in just over 3 weeks we won't ever touch A levels again.
    I'm going to miss 6th form but can't wait for Uni aswell.
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    (Original post by XxKingSniprxX)
    How many exams has everyone got left?

    I've got 8 exams -> 4 maths, 3 physics and 1 history.
    2/10 exams finished atm.

    Crazy in just over 3 weeks we won't ever touch A levels again.
    I'm going to miss 6th form but can't wait for Uni aswell.
    11 left (5 maths, 2 chem, 2 bio, 2 physics), had one maths so far. Literally can't wait to start exams feel like this week was just a week of waiting for exams (ofc with lots of revision thrown in!)
    What I'm most looking forward to is people asking me out and me not having to cancel/feel guilty about it!! Haven't really had a summer "off" since end of year 10 so it's been three years of being "too busy" for me... Actually so excited :')
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    (Original post by XxKingSniprxX)
    How many exams has everyone got left?

    I've got 8 exams -> 4 maths, 3 physics and 1 history.
    2/10 exams finished atm.

    Crazy in just over 3 weeks we won't ever touch A levels again.
    I'm going to miss 6th form but can't wait for Uni aswell.
    I finished last week.

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